According to MacRumours , the crashing feature happens when users attempt to make large file transfers.

In a forum post, SoftRAID described the issue as a bug and said that it is working with Apple engineers on a fix for macOS 10.15.5, or a workaround. Of course, saying it is “just a bug” didn’t help Boris Johnson and it is not going to really help Apple here.

SoftRAID said the issue extends to Apple-formatted disks and is a serious issue. It shows up where there are many IO threads and is probably a threading issue. 

“So while SoftRAID volumes are hit the hardest (its now hard to copy more than 30GB of data at a time), all systems are impacted by this”, the outfit said.

In its bug report to Apple, the company said: "We used a method to reproduce the problem with ONLY Apple formatted disks. Takes longer to reproduce, but that is more likely to get a faster fix to the user base."

Other users on macOS 10.15.4 have experienced crashes after waking their Mac from sleep, with affected systems suffering a kernel panic and rebooting to the Apple logo, according to comments shared on the Apple Support Communities, MacRumors Forums, Reddit, and Twitter. But it is the sort of quality they pay large amounts of money to get, so they are used to it.

After updating to macOS 10.15.4, users may also experience continuous spinning up and spinning down of connected hard drives when a Mac is supposed to be asleep, which could result in damage to the drive, according to Jeremy Horwitz.

Of course, the spinning might just be caused by the Apple fanboy’s wife/mother seeing the credit card bill for Apple gear which has buggy software.